An organic light-emitting display substrate includes a substrate, and an anode electrode layer, a light emitting functional layer and a cathode electrode layer which are arranged on the substrate. In a manufacturing process of an organic light-emitting display substrate, a light emitting functional layer can be formed on an anode electrode layer by inkjet printing. Considering the fluidity of ink, a pixel defining layer is generally arranged in non-pixel areas between the pixel pattern areas in order to reduce overflow of the ink for inkjet printing to adjacent pixel pattern areas. The pixel defining layer is provided with a plurality of openings corresponding to pixel units, and light emitting functional layer ink is spray coated in the openings by inkjet printing.
With regard to equipment including a large-sized organic light emitting display device, generally the size of an inkjet head for inkjet printing cannot be equivalent to the width of a display area due to technical limits. Therefore, the inkjet head needs to repeatedly sweep on a panel for many times so as to accomplish printing the entire panel. After each printing action, the organic solvent in the ink volatilizes to a certain extent, and given the ambiences of the printing area are inconsistent, the volatilization speeds of the organic solvent in the pixel units of the entire printing area are different. Generally, the organic solvent in the pixel unit close to a non-printing area (i.e., the pixel unit at the boundary of the printing area) volatilizes faster, and the organic solvent in the pixel unit away from the non-printing area (i.e., the pixel unit in the interior of the printing area) volatilizes slower, so that the film forming effect at the boundary of the printing area is different from that in the interior of the printing area, and swatch mura is further formed on the lightened panel.